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drug information


Cannabis is a drug that comes from the sativa plant. the main active chemical in cannabis is THC (delta-9 tetrahydrocannabional). There are three main forms of cannabis: marijuana, hashish and hash oil. Marijuana is the most common and least powerful form of cannabis, consisting of the dried leaves and flowers of the plant.

  1. What it is

    Cannabis is a drug that comes from the cannabis sativa plant. Its active compound is Delta-9 tetrahydrocannabinol (THC). The higher a plant is in THC, the stronger its effects will be.

  2. Health effects

    Short-term effects

    The effects of smoking small amounts of cannabis include

  3. Dependence, addiction and overdose risk

    Dependence and addiction

    Cannabis can be physically and psychologically addictive. Someone is said to be dependent on cannabis when they experience three or more of these six criteria over a year:

  4. Law and penalities

    It is illegal to import, grow, sell, distribute, possess and use cannabis in New Zealand. People can be charged under the Misuse of Drugs Act 1975.

  5. Drug trends

    Cannabis is the most widely used illicit drug in New Zealand and nearly half (42%) of all adults over 15 have tried it.

    The latest research from the New Zealand Health Survey 2012/13 published in 2015 shows that:

  6. Reducing the harm

    The Drug Foundation’s message is clear: no drug use is the safest drug use. However, we know there will be occasions when people ignore warnings and use drugs in a dangerous manner. To help keep communities safe we therefore provide information about proven methods of drug harm reduction.

  7. How to get help

    If you feel you or anyone you know needs help, there are a number of treatment organisations you can contact in strict confidence.

  8. Medical cannabis

    The scientific and clinical evidence to support the medical use of cannabis and cannabis-derived products is still limited. Much of the research to date has been with very small patient groups, used different cannabis products at different doses and/or has not compared the new cannabis treatment against standard treatment.

    On this page is a summary of issues surrounding access to and use of medical cannabis, and a detailed Q&A was added in December 2015.  

  9. Cannabis and psychosis

    There is growing evidence reliably linking cannabis with mental health problems. However, it remains unclear whether cannabis actually causes mental illness, or whether many people with mental illness are pre-disposed towards cannabis use.

  10. The Gateway theory

    Some argue cannabis is a gateway drug – that its use causes people to also try, more dangerous drugs. This argument is often used to justify ongoing criminalisation of cannabis.